Research And Implementation On Live Streaming System Based On P2P Technology

In recent years, with the widely used of network and rapid development on broadband, network multimedia technology is developing greatly which is highly stricted with network bandwidth. Among them, the multimedia technology based on P2P network is becoming the hotspot. Using the complete distributional construction on P2P technology, the nodes in internet can not only get but also provide resources or services from others. The live streaming system with P2P technology can reduce not only the server resources and bandwidth effectively but also the deployment cost. But the existing systems still have some problems to solve, including: network relay, uncontrollable network, asymmetrical transmission, NAT traversal, security and management.Deeply research on several basic issues on P2P live streaming system were presented in this thesis, including the design of overlay network, managing and maintaining nodes, scheduling dynamic data set between data sending nodes to obtain minimum delay, and etc. Within the above issues, a system called PolyTV was designed to demonstrate a well organized P2P media streaming system. The main issues and contributions of this dissertation are as following:Firstly, a plan for application layer multicast was proposed, which harnessed the heterogeneity of the nodes to main topology by gossip protocol. And aiming at the issues of NAT for p2p network, a novel method was shown to improve NAT traversal rate, which could make nodes after symmetric NAT communicate to increase the rate of resources in p2p network.Secondly, a new algorithm called LFSA was introduced to dynamic scheduling data distribution among sets of partner nodes, which relied on the resources allocation and computes the'data retrieving set'dynamically. With the consideration of node load and network delay, it controlled the sequence of data sending nodes, which resulted in a balanced load network and low bandwidth cost.Finally, a P2P live streaming system called PolyTV was designed and implemented. A lot of experimental data showed that this system can reduce control overhead, data scheduling delay, and improve the reliability. It can be used in actual application.